Wednesday, June 8, 2011

June Vacation Chap 9.2 RATE (L4) Self-Paced Learning

1. Mathematics Textbook 1B
(a) Go through Chapter 9 (p9 to p11)
(b) Attempt Exercise 9.2 Q1 to Q10.
Enter your answers to Exercise 9.2 under Comments. Label your Answers with Question numbers.

2. ACELearning Portal: eLearning Portal
> Subject: Secondary 1 Express
> Additional Arithmetic
> Ratio, Rate and Speed: Choose Rate

(a) Go through video lessons: Rate, Average Rate, Example 1, Example 2
(b) Try Practice Drills on your own to check your understanding
Note: An email has been sent to all students via the AceLearning

20 comments:

  1. Answers :

    1a - $3.50
    1b - 72 vases/day
    1c - 47 words/min
    1d - $80/m²
    1e - 4kg/m
    1f - 60g/egg

    2a - $23/hr
    2b - $920/week

    3a - 9km/litre
    3b - $1.20/litre

    4a -87.5g
    4b - 125cm³

    5a - $15
    5b - $150

    6a - $22.50/m²
    6b - $450

    7a - 27 litres/minute
    7b - 3 minutes

    8a - $26/kg
    8b - 25g

    9a - $201 600
    9b - $4200/m²

    10a - 19.3g
    10b - 2cm x 2cm x 2cm = 8cm³

    27cm³ -> 521.1g
    8cm³ -> 8/27 x 521.1g = 154.4g
    154.4g > 120g

    Explanation : No, it is not made from pure gold. The gold cube is not pure gold as it is lighter than pure gold when it is at 8cm³. At 8cm³, the pure gold should weigh in at 154.4g. This gold cube weighs 120g which is lighter than the pure gold cube. Therefore, it is not pure gold.

    ReplyDelete
  2. ============================
    Exercise 9.2
    ============================
    1a) A 2-litre bottle of peanut oil costs $7

    2 litre of peanut oil cost -> $7
    1 litre of peanut oil cost -> $7 ÷ 2 = $3.50

    The price rate is $3.50 / litre
    ============================
    1b) A company produces 360 vases in 5 days.

    5 days -> 360 vases
    1 day -> 360 ÷ 5 = 72 vases

    The rate of production is 72 vases/day.
    ============================
    1c) Huili typed 376 words in 8 minutes.

    8 minutes -> 376 words
    1 minute -> 376 ÷ 8 = 47 words

    Her rate of typing is 47 words/min
    ============================
    1d) A carpet of area 3m² costs $240.

    3m² -> $240
    1m² -> $240 ÷ 3 = $80

    The price rate is $80 / m²
    ============================
    1e) The mass of a 2.5-m metal bar is 10kg.

    10kg / 2.5m = 4kg / m

    The rate of mass is 4 kg/m
    ============================
    1f) The mass of 12 eggs is 720g.

    12 eggs -> 720g
    1 egg -> 720g ÷ 12 = 60g

    The rate of mass is 60g/egg.
    ============================
    ============================
    2) Rahman works 5 days a week and 8 hours a day. His daily wage is $184.
    a) Find his hourly wage rate.

    $184 ÷ 8 = $23 / hr

    His hourly wage rate is $23/hr
    -----------------------------------------
    a) Find his weekly wage rate.

    $184 x 5 = $920/week
    ============================
    ============================
    3) A car travelled 225 km on 25 litres of petrol. The price of petrol consumed was $30.
    a) Find the rate of petrol consumption in km/litre.

    225/25litre = 9km/litre

    The rate of petrol consumption is 9km/litre.
    -----------------------------------------
    a) What was the price of petrol per litre?

    $30/25 litre = $1.20/litre

    The price of petrol is $1.20/litre
    ============================
    ============================
    4) There are 6 wooden cubes, each of side 5cm. Their total mass is 525g. Find the mass per :
    a) cube,

    525g ÷ 6 = 87.5g

    The mass of one cube is 87.5g.
    -----------------------------------------
    b) cm³ of cube.

    5cm x 5cm x 5cm = 125cm³

    The volume of one cube is 125cm³.
    ============================
    Further Practice
    ============================

    5)John spent $120 on 8 concert tickets.
    a) Find the price per ticket.

    8 Concert Tickets -> $120
    1 Concert Ticket -> $120 ÷ 8 = $15

    The price of 1 concert ticket is $15.
    -----------------------------------------
    b) Find the price of 10 tickets.

    8 Concert Tickets -> $120
    10 Concert Tickets -> 10/8 x $120 = $150

    10 Concert Tickets costs $150.
    ============================
    ============================
    6) The price of laying 12m² of floor tiles is $270.
    a) Find the price of laying floor tiles per m².

    12m² -> $270
    1m² -> $22.50
    The price of laying floor is $22.50/m².
    -----------------------------------------
    b) Find the price of laying 20 m² of floor tiles.

    12m² -> $270
    20m² -> 20/12 x $270 = $450

    The price of laying 20m² is $450
    ============================
    ============================
    7) A pipe delivers 9 litre of water in 20 seconds.
    a) Find the amount of water it delivers per minute.

    1 minute = 60 seconds
    60 seconds ÷ 20 seconds = 3
    3 x 9 litres = 27 litres

    The pipe can deliver 27 litres per minute.
    -----------------------------------------
    b) An empty fish tank is 60 cm long, 45 cm wide and 30 cm high. How long does it take for the pipe to fill the empty tank completely with water?
    (1 litre = 1000 cm³)

    Volume = 60cm x 45 cm x 30 cm = 81000cm³
    81000cm³ = 81 litres
    81 litre ÷ 27 litre = 3 minutes

    It would take 3 minutes to fill the empty tank.

    ReplyDelete
  3. WORKINGS (Part 2)


    ============================
    Maths @ Work
    ============================
    8) A 500-g pack of fertiliser that costs $13 can be applied to 20 m² of lawn.
    a) What is the cost of the fertiliser per kg?

    1kg = 1000g
    1000g ÷ 500g = 2
    2 x $13 = $26

    The fertiliser cost $26/kg
    -----------------------------------------
    b) Find the mass of the fertiliser that can be applied to 1m² of lawn.

    500g ÷ 20m² = 25g/m²

    25g of fertiliser can be applied to 1m² of lawn.
    -----------------------------------------
    a) A rectangular lawn measures 15m by 8m. Find the mass and cost of the fertiliser required for the lawn.

    15m x 8m = 120m²
    120m² ÷ 20m² = 6
    6 x $13 = $78
    6 x 500g = 3000g
    3000g = 3kg

    The cost and the mass of the fertiliser is $78 and 3kg respectively.
    ============================
    ============================
    9) The price of an apartment of area 120 m² is $504 000. Jenny and her mother shared the cost of such an apartment in the ratio 2 : 3.
    a) How much did Jenny pay?

    2 + 3 = 5
    2/5 x $504 000 = $201 600

    Jenny paid $201 600 for the apartment
    -----------------------------------------
    b) What was the price per m² of the apartment?

    $504 000 ÷ 120m² = $4200/m²

    1m² costs $4200
    ============================
    ============================
    10) A pure gold cube is of side 3cm. Its mass is 521.1 g.
    a) Find the mass of pure gold per cm³.

    3cm x 3cm x 3cm = 27 cm³
    27cm³ -> 521.1g
    1cm³ -> 19.3g

    1cm³ of pure gold weighs 19.3g
    -----------------------------------------
    b) Another gold cube is of side 2cm. Its mass is 120 g. Is it made of pure gold? Explain briefly.

    2cm x 2cm x 2cm = 8cm³

    27cm³ -> 521.1g
    8cm³ -> 8/27 x 521.1g = 154.4g
    154.4g > 120g

    Explanation : No, it is not made from pure gold. The gold cube is not pure gold as it is lighter than pure gold when it is at 8cm³. At 8cm³, the pure gold should weigh in at 154.4g. This gold cube weighs 120g which is lighter than the pure gold cube. Therefore, it is not pure gold.

    ReplyDelete
  4. 1a) 7/2
    = $3.50/litre

    1b) 360/5
    = 72 vases/day

    1c) 376/8
    = 47 words/min

    1d) 240/3
    = 80/m²

    1e) 10/2.5
    = 4kg/m

    1f) 720/12
    = 60g/egg

    2a) 184/8
    = $23/hour

    2b) 184 X 5
    = $920/week

    3a) 225/25
    = 9km/litre

    3b) 30/25
    = $1.20/litre

    4a) 525/6
    = 87.5/cube

    4b) 5x5x5=125 cm³
    87.5/125
    = 0.7g/cm³

    5a) 120/8
    = $15/ticket

    5b) 15 X 10
    = $150/10 tickets

    6a) 270/12
    = $22.50/m²

    6b) 22.50 X 20
    = $450/20m²

    7a) 9 X 3
    = 27litres/min

    7b) 60 X 45 X 30 = 81,000 cm³ = 81 litres
    81/27
    = 3 minutes to fill the tank completely with water

    8a) 13 X 2
    = $26/kg

    8b) 500/20
    = 25g/m²

    8c) 15 X 8 = 120m²
    500 X 6 = 3000g
    = 3kg
    $13 X 6
    = $78

    9a) 504,000/5 X 2
    = $201,600

    9b) 504,000/120
    = $4200/m²

    10a) 3 X 3 X 3 = 27cm³
    52.11/27
    = 19.3g/cm³

    10b) 2 X 2 X 2 = 8cm³
    120/8
    = 15g/cm³

    It is not made out of pure gold because it has a lower mass to cm³ rate than the 1st cube

    ReplyDelete
  5. 1. (a)$3.50/litre
    (b)72 vases/day
    (c)47 words/min
    (d)$80 /m^2
    (e)4kg /m
    (f)60g /egg

    2. (a)$23 /hour
    (b)$92 0/week

    3. (a)9 KM /litre
    (b)$1.20 /litre

    4. (a)87.5g/cube
    (b)0.7g/cm^3 of cube

    5. (a)$15 /ticket
    (b)$50

    6. (a)$22.50/m^2
    (b)$450

    7. (a)27 liters/minute
    (b)3 minutes

    8. (a)$26/Kg
    (b)25g
    (c)mass=3Kg
    cost=$78

    9. (a)$201000
    (b)$4200/m^2

    10.(a)19.3g/cm^3

    Explanation:
    (b)its not made of pure gold because the gold cube's mass per cm^3 is 15 while the mass of pure gold per cm^3 is 19.3g.

    ReplyDelete
  6. Basic Practice
    ============
    1 (a) $7 / 2l = $3.50/l

    (b) 360 / 5 = 72vases/day

    (c) 376words / 8minutes = 47words/min

    (d) $240 / 3m^2 = $80/m^2

    (e) 10kg / 2.5m = 4kg/m

    (f) 720g / 12eggs = 60g/egg

    2 (a) $184 / 8hr = $23/h

    (b) $184 X 5days(week) = $920/week

    3 (a) 225km / 25l = 9km/litre

    (b) $30 / 25l = $1.2/l

    4 (a) 525g / 6cubes = 87.5g/cube

    (b) 5^3 = 125cm^3
    87.5g / 125cm^3 = 0.7g/cm^3
    -------------------------------
    Further Practice
    -------------------------------

    5 (a) $120 / 8tickets = $15/ticket

    (b) $15 X 10 = $150

    6 (a) $270 / 12m^2 = $22.50/m^2

    $22.50 X 20m^2 = $450

    7 (a) 9l X 3 = 27l/min

    (b) 60cm X 45cm X 30Cm = 81l
    81l / 27l = 3mins

    8 (a) $13 X 2 = $23/kg

    (b) 500g / 20m^2 = 25g

    9 (a) $504000 / 5 X 2 = $201600

    (b) $504000 / 120m^2 = $4200/m^2

    10 (a) 3x3x3=27
    521.1g / 27cm^3 = 19.3g/cm^3

    (b) Mass/cm^3 of the GOLD cube is 15g/cm^3
    Mass/cm^3 of the PURE GOLD cube is 19.3g/cm^3
    the both masses are different and therefore the other gold cube is not made of pure gold.

    ReplyDelete
  7. 1.
    (a)$3.5/litre
    (b)72vases/day
    (c)47words/min
    (d)$80/m^2
    (e)4kg/m
    (f)60g/egg

    2.
    (a)$23/hour
    (b)$920/week

    3.
    (a)9km/litre
    (b)$1.20/litre

    4.
    (a)87.5g/cube
    (b)4.2g/cm^2

    5.
    (a)$15/ticket
    (b)$150/ticket

    6.
    (a)$22.5/m^2
    (b)$450

    7.
    (a)27litre/min
    (b)60x45x30 = 81000
    81000÷1000 = 81
    81÷27 = 3
    3mins

    8.
    (a)$261kg
    (b)25g
    (c)Mass:3Kg
    Cost:$78

    9.
    (a)$201600
    (b)$4200/m^2

    10.
    (a)19.3g/cm^3
    (b)pure gold cube = 174g/cm
    "gold cube" = 60g/cm
    No. The rate of the mass per cm of the "gold cube" is lesser than the pure gold cube, thus it is to light to be a gold cube.

    ReplyDelete
  8. 1a) $7÷2=$3.50 / l
    1b) 360÷5=72 vases/day
    1c) 376÷8=47 words/min
    1d) $240÷3m²=$80/m²
    1e) 10÷2.5=4 kg/m
    1f) 720÷12=60 g/egg

    2a) $184÷8h=$23/h
    2b) $184 x 5 days=$920/week

    3a) 225km÷25l =9km / l
    3b) $30÷25l =$1.2 / l

    4a) 525÷6=87.5g/cube
    4b) 5m x 5cm x 5cm=125cm³

    5a) $120÷8=$15/concert ticket
    5b) $15 x 10=$150

    6a) $270÷12m²=$22.50/m²
    6b) $22.50 x 20m²=$450

    7a) 9l /20s x 3=27l/min
    7b) 60cm x 45cm x 30cm=40500ml 27l/min =27000ml/min 40500ml÷27000ml/min=1.5min

    8a) $13/500g x 2=$26/kg
    8b) 500g÷20=25g/m²
    8c) 15m x 8m=120m² 120m² x 25g/m²=3000=3kg $26/kg x 3kg=$78

    9a) $504000÷5x2=$201600
    9b) $504000÷120m²=$4200/m²

    10a) 3³cm=27cm³ 521.1÷27cm³=19.3g/m³
    10b) No. Pure gold is 19.3g/m³, while the smaller cube of gold is 15g/m³, soit is not pure gold. 2³cm=8cm³ 120g÷8cm³=15g/m³

    ReplyDelete
  9. This comment has been removed by the author.

    ReplyDelete
  10. (1) ⎮ ANS
    (1a)$7 /2Litre
    $3.5/L
    (1b)360 vases/5day
    72vases/day
    (1c)376 words/8minutes
    47words/min
    (1d)$240/3m^2
    $80/m^2
    (1e)10Kg/2.5m
    4Kg/m
    (1f)720g/12eggs
    60g/egg

    ==================================================
    (2)
    (2a)$184÷8=$23
    $23/hr
    (2b)$184×5=$920
    $920/week
    ==================================================
    (3)
    (3a)225Km÷25Litres
    9Km/Litre
    (3b)$30÷25litres
    $1.20/litre
    ==================================================
    (4)
    (4a)525g÷6cubes
    87.5g /cube
    (4b)5cm×5cm×5cm
    125 cm∗3
    ==================================================
    (5)
    (5a)$120÷8tickets
    $15/ticket
    (5b)$15×10tickets
    $150
    =================================================

    ReplyDelete
  11. 1a) $3.50/l
    1b) 72vases/day
    1c) 47words/min
    1d) $80/m^2
    1e) 4kg/m^2
    1f) 60g/egg

    2a) $23
    2b) $920

    3a) 9km/l
    3b) $1.20/l

    4a) 87.5g
    4b) 4.2g/cm^3

    5a) $15
    5b) $150

    6a) $22.5/m^2
    6b) $450

    7a) 27l/min
    7b) 3min

    8a) $26/kg
    8b) 25g
    8c) 3kg

    9a) $201600
    9b) $4200

    10a) 19.3g/cm^3
    10b) No. It is because the mass per cm^3 is only 15g/cm^3, not 19.3g/cm^3

    ReplyDelete
  12. (6)
    (6a)$270/12m*2
    $22.50
    (6b)$22.50x12
    $450
    ==================================================
    (7)
    (7a)9Litres x3
    27litres
    (7b)60cm x45cm x30cm=81000cm*3
    81000cm*3/1000=81litres
    81litres/9=9
    9x20sec=180sec
    ANS:180sec
    ==================================================
    (8)
    (8a)$13x2
    $26
    (8b)500g/20
    25g
    (8c)15mx8m=120m*2
    120m*2/20=6
    6x13=78
    6x500=3000
    ANS:
    mass:3000g
    cost:$78
    ==================================================
    (9)
    (9a)504000x2/5=201600
    $201600
    (9b)504000/120=4200
    $4200/m*2
    ==================================================(10)
    (10a)3x3x3=27
    521/27=19.39
    ANS:19.39g/cm*3
    (10b)2x2x2=8
    120/8=15
    15cm*3
    the cube with the side of 2 cm is not pure gold as the cm*3 for pure gold is 19.39cm*3, but it is 15cm*3

    ReplyDelete
  13. 1a)$3.50/l
    b)72vases/day
    c)47words/min
    d)$80/m*2
    e)4kg/m
    f)60g/egg

    2a)$23
    b)$920

    3a)9km/l
    b)$1.20/l

    4a)87.5g/cm*3
    b)0.7g/cm*3

    5a)$15/ticket
    b)$150

    6a)$22.50/m*2
    b)$450

    7a)27l/min
    b)3min

    8a)$26/kg
    b)25g/m*2
    c)i)300g
    ii)$78

    9a)$201600
    b)$4200/m*2

    10a)19.3g/cm*3
    b)No. The mass of the pure gold cube is 19.3g/cm*3 while the mass of the gold cube is 15g/cm*3 which makes the gold cube lighter and is not pure gold as mass to volume ratio of pure gold to the gold cube is different.

    ReplyDelete
  14. Basic practice
    --------------
    1.
    a) $3.5/L
    b) 72 vases/day
    c) 47 words/min
    d) $80/m²
    e) 4 kg/m
    f) 60 g/egg

    2.
    a) $23
    b) $920

    3.
    a) 9 km/L
    b) $1.2/L

    4.
    a) 87.5 g/cube
    b) 0.7 g/cm³

    5.
    a) $!5/ticket
    b) $150

    6.
    a) $22.50/m²
    b) $450

    7.
    a) 27 L/min
    b) 3 min

    8.
    a) $13 x 2 = $26
    b) 25g
    c) (15 x 8)m² = 120m²
    mass = 25 x 120g = 3kg
    cost = 26 x 3 = $78

    9.
    a) 2/(2+3) x $504000 = $201600
    b) $504000 ÷ 120 = $4200

    10.
    a) 521.1 ÷ 3³ = 19.3 g/cm³
    b) 120 ÷ 2³ = 15 g/cm³

    ReplyDelete
  15. 1a)$3.50 per litre
    1b)72 vases per day
    1c)47 words per min
    1d)$80/m²
    1e)4kg/m
    1f)60g/egg

    2a)$23/hr
    2b)$920/week

    3a)9km/litre
    3b)$1.20/litre

    4a)87.5g
    4b)125cm³

    5a)$15
    5b)$150

    6a)$22.50/m²
    6b)$450

    7a)27 litres/minute
    7b)3 minutes

    8a)$26/kg
    8b)25g
    8c)3kg

    9a)$201600
    9b)$4200/m²

    10a)19.3g/cm³
    10b)No. It is because the mass of the cube per cm³ is only 15g/cm³, not 19.3g/cm³.Therefore, it is not pure gold.

    ReplyDelete
  16. 1) a) $7 / 2 l = $3.50/l l
    b) 360 vases / 5 days = 72 vases/days
    c) 376 words / 8 min = 47 words/min
    d) $ 240 / 3 m^2 = $80 / m/62
    e) 10 kg / 2.5 m^2 = 4kg / m^2
    f) 720 g / 12 eggs = 60 g / g

    2) a) $/hours = $184 / 8h = $23/ h
    b) $/weeks = $184 x / 1 weeks = $920 / 1 week

    3) a) km / litres = 225km / 25 l =9km/ litres
    b) $ / litres = $ 30 / 25 l ~ (sry no equivalent sign) $1.20/ litres

    4 a) g/ cube = 525 g/ 6cubes = 87.5 g/ cube
    b) g/ cm^3 = 87.5g / 5 x 5 x5 cm ^ 3 =
    =87.5g / 125 cm^3
    =0.7 g / m^3

    5) a) $ / Ticket = $ 120 / 8 ticket = $15/ ticket
    b) $15/ ticket x 10 = $150


    6) a) $/ m ^ 2 = $270 / 12 m^2
    = $22.5
    b) $22.50 / m^2 x 20 m^2 = $450

    7 ) a) 9 l /20s = 27 l /60s = 27 l / min
    b) Time = Vol / Rate =
    = (60 x 45 x 30 )cm ÷ 27 l /min
    = 81000 cm ^ 3 ÷ 27 l / min
    = 81 l ÷ 27 l / min

    8) a) $ / kg = $13 / 500 g =$13 / 0.5 kg
    =$ 26 / kg
    b) g / m^2 = 500 g / 20m^2 =25g / m^2
    c) Rate x m^2 = 25g /m ^2 x (15m x 8m)
    = 3000g
    Rate x kg = $26 / kg x 3kg
    = $78

    a) $50400 x / (2 + 3) = $201600
    b) Rate : $ /m^2 =$504000 / 12 m^2
    =$4200 / m^2

    10) a) Rate : g /cm ^3 = 521.1g /3 x3 x3 cm^3
    = 521.1g / 27 cm^3
    = 19.3 g/ cm ^3

    b) Density: g /cm^3 = 120g /( 2 x 2 x 2)
    = 15g/ cm ^ 3
    No it is not, its density is different from pure gold


    Sherman

    ReplyDelete
  17. 1a:$3.50
    1b:72 vases/day
    1c:47words/min
    1d:$80/m^2
    1e:4 kg/m
    1f: 60 g/egg
    2a:$23/hour
    2b:$920/week
    3a: 9km/litre
    3b:$3.30/litre
    4a:87.5g/cube
    4b:0.7 g
    5a: $15/ticket
    5b:$150
    6a:$22.50/m^2
    6b:$450
    7a: 27 litre/min
    7b: 3 min
    8a:$26
    8b:25g
    8c:$1208
    9a:$201600
    9b:$4200/ m^2
    10a:19.3g/cm^3
    10b: no the density is 120g/cm^3 but a pure gold cube is 19.3g/cm^3

    ReplyDelete
  18. Charles O'Rourke6/26/2011 08:22:00 PM

    1. a)$3.50/litre

    b)72 vases/day

    c)47 words/min

    d)$80/m2

    e)4kg/m

    f)6g/egg
    -------------
    2.a)$23/hour

    b)$920/week

    3.a)9 KM /litre

    (b)$1.20 /litre

    4. (a)87.5g/cube

    (b)0.7g/cm^3 of cube

    5. (a)$15 /ticket

    (b)$150

    6. (a)$22.50/m2

    (b)$450/

    7. (a)27 l/min

    (b)3 min

    8. (a)$26/Kg

    (b)25g

    (c)mass=3Kg
    cost=$78

    9. (a)$20100

    (b)$4200/m2

    10.(a)19.3g/cm3

    Explanation:
    (b)The gold cube's mass for ever cm3 is 15 not 19.3g for every cm3 which is the pure gold;s mass

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  19. 1a. 3.50
    1b. 72
    1c. 47
    1d. 80
    1e. 4
    1f. 60
    2a. $23/hour
    2b. $920/week
    3a. 9km/litre
    3b. $1.20/litre
    4a. 87.5g
    4b. 125cm³
    5a. $15
    5b. $150
    6a. $22.50/m²
    6b. $450
    7a. 27 litres/minute
    7b. 3 minutes
    8a. $26/kg
    8b. 25g
    9a. $201600
    9b. $4200/m²
    10a.19.3g
    10b. No, it is not. Pure gold's mass is 19.3g/cm3 but this gold in the gold cube has a mass of 15g/cm3 which is not the same as pure gold so it is not pure gold.

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  20. 1a.$3.50/litre
    1b.72 vases/day
    1c.47words/min
    1d.$80/m^2
    1e.4 kg/m
    1f. 60 g/egg
    2a.$23/hour
    2b.$920/week
    3a.9km/litre
    3b.$3.30/litre
    4a.87.5g/cube
    4b.0.7 g/m^3
    5a.$15/ticket
    5b.$150
    6a.$22.50/m^2
    6b.$450
    7a. 27 litres/min
    7b. 3 min
    8a.$26
    8b.25g
    8c.$1208
    9a.$201600
    9b.$4200/ m^2
    10a.19.3g/cm^3
    10b. No, because the density of the gold cube is 15g/cm^3, while pure gold's is 19.3g/cm^3.

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